ENST00000350092.8:c.2T>C

Variant names:

• chr19-803613-T-C
• ENST00000350092.8:c.2T>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PVS1_Supporting PM2

The ENST00000350092.8(PTBP1):​c.2T>C​(p.Met1?) variant causes a start lost change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,836 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: PTBP1 ENST00000350092.8 start_lost
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.50
• Publications: 0 publications found

Genes affected

PTBP1 (HGNC:9583): (polypyrimidine tract binding protein 1) This gene belongs to the subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). The hnRNPs are RNA-binding proteins and they complex with heterogeneous nuclear RNA (hnRNA). These proteins are associated with pre-mRNAs in the nucleus and appear to influence pre-mRNA processing and other aspects of mRNA metabolism and transport. While all of the hnRNPs are present in the nucleus, some seem to shuttle between the nucleus and the cytoplasm. The hnRNP proteins have distinct nucleic acid binding properties. The protein encoded by this gene has four repeats of quasi-RNA recognition motif (RRM) domains that bind RNAs. This protein binds to the intronic polypyrimidine tracts that requires pre-mRNA splicing and acts via the protein degradation ubiquitin-proteasome pathway. It may also promote the binding of U2 snRNP to pre-mRNAs. This protein is localized in the nucleoplasm and it is also detected in the perinucleolar structure. Alternatively spliced transcript variants encoding different isoforms have been described. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PVS1: Start lost variant, no pathogenic variants between lost start and next in-frame start position. Next in-frame start position is after 60 codons. Genomic position: 804188. Lost 0.112 part of the original CDS.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
PTBP1	NM_002819.5	c.92T>C	p.Met31Thr	missense_variant	Exon 3 of 15	ENST00000356948.11	NP_002810.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
PTBP1	ENST00000356948.11	c.92T>C	p.Met31Thr	missense_variant	Exon 3 of 15	1	NM_002819.5	ENSP00000349428.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461836 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727220

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111982

Other (OTH) AF: 0.00 AC: 0 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Apr 28, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.92T>C (p.M31T) alteration is located in exon 3 (coding exon 3) of the PTBP1 gene. This alteration results from a T to C substitution at nucleotide position 92, causing the methionine (M) at amino acid position 31 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Uncertain	24
DANN	Benign	0.92
DEOGEN2	Benign	0.37	.;.;T;.;.;T;T;.
Eigen	Benign	-0.020
Eigen_PC	Benign	0.043
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.92	D;D;D;D;D;D;D;D
M_CAP	Benign	0.075	D
MetaRNN	Benign	0.39	T;T;T;D;T;T;T;D
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	1.9	L;.;L;.;L;.;.;.
PhyloP100		7.5
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-2.7	D;.;D;.;D;.;.;N
REVEL	Benign	0.27
Sift	Uncertain	0.024	D;.;D;.;D;.;.;D
Sift4G	Benign	0.14	T;T;T;D;T;T;D;D
Polyphen		0.67, 0.32	.;.;P;.;B;.;.;.
Vest4		0.89
MutPred		0.27		Gain of loop (P = 0.0079);Gain of loop (P = 0.0079);Gain of loop (P = 0.0079);.;Gain of loop (P = 0.0079);Gain of loop (P = 0.0079);.;.;
MVP		0.85
MPC		0.63
ClinPred		0.81	D
GERP RS		4.5
PromoterAI		-0.0026	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.55
gMVP		0.53
Mutation Taster		=58/42	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

hg19: chr19-803613;